Lubricating composition



Patented Apr. 25, 1944 UNITED STATES PATENT OFFICE;

LUBRICATING COMPOSITION Carl F. Prutton, Cleveland, and Albert K. Smith,

Shaker Heights, Ohio, assignors, by mesne assignments, to The Lu'bri-ZolDevelopment Corporation, Cleveland, Ohio, a-c'orporation of Delaware NoDrawing. Application December 19, 1940',

Serial No. 370,838

4 Claims. (01. 252-423) for the purpose of reducing friction betweenrelatively movable metallic parts functions in two ways commonlyreferred to as thick-film lubrication and thin-film lubrication.

In thick-film lubrication the bearing surfaces are completely separatedby a relatively thick continuous film of the lubricating compositionemployed. When friction between the moving parts is measured in thiscase, the resuits obtained are independent of all factors exceptpressure, speed and the viscosity of the lubricating composition. Asingle curve representing all data may be found by plotting thecoeflicient of friction against a particular function consisting of theproduct of the viscosity of the lubricating composition andthe speed" ofrelative movement of the parts divided by the pressure per unit area ofthe bearing surface, as long as the value of such function is greaterthan a definite amount. At this minimum point, reduction of viscosity orspeed or an increasein the pressure results in a breaking down of thefilm of lubricant. Although the value of the co emcient of friction islowest at the point atwhich the film is about to break down, theincrease in the coeflicient for higher viscosity and speed or lowerpressure is relatively slight. The conditions resulting in thick-filmlubrication are, therefore, those which result in low friction.

For pressures suificiently great or for correspondingly low values ofviscosity or speed, the

film of lubricant, as above indicated, is broken down and if it is notentirely destroyed, the metallic bearing surfaces are still affected tosome extent, at least by the presence of the lubricating composition.This condition is commonly referred to as thin-film" lubrication.

When one of the bearing surfaces is a metal such as bronze or babbitt,seizure does not take place at once but the coefficient of frictionincreases rapidly to abnormally high values with each slight furtherincrease in pressure or decrease in viscosity or speed. For a given setof bearings the data obtained for thin-film" lubrication may beapproximately coordinated into a single curve but only on plottingcoefficient of friction against the product of viscosity and speeddivided by the square root of the pressure.

the description proceeds.

If both bearing surfaces are of steel,"-seizure" or scoring will resultalmost immediately upon failure of thick-film" lubrication when a puremineral oil is the sole lubricating composition employed.

It is among the objects of our vide' a lubricating composition which maybe employed to reduce the friction betweenrelatively movable metallicsurfaces under pressures and other factors which result in-what has beenabove explained asthick-film lubrication and a composition which may beemployed for suchthin-film lubrication and without a material increasein' the coeflicient of friction between the parts over that found duringthick-film lubrication; 7

Other objects of our invention ,willappear as To the accomplishment ofthe foregoing and related ends, saidinvention, then, consists of themeans'hereinafter fully described and particularly pointed out' n theclaims.

The following description sets forth in detail one approved combinationof ingredients embodying our invention, such disclosed meansconstituting, however, but one of various forms'in which the principleof the invention may be used.

Broadly stated, this invention comprises incorporating certain forms ofhalogenated carbon compounds'with certain types of oil bases. Morespecifically, the invention comprises incorporating a halogenated carboncompound with a sulphur treated oil base.

By the term sulphur treated oil" as employed in this description, ismeant" any suitable oil base which has been treated with sulphur, forexample, the composition produced by heating sulphur with a fixed oil,such as lard oil or fish oil; or to which sulphur or a sulphur compound,(e. g. di-phenyl d-i-sulphide) has been added, so

that a certain amount of sulphur is present in' active or looselycombined-form. It has been found that a suitable oil base containingfrom 0.50% to 2.50% of sulphur in active or loosely combinedform is bestsuited for use in a composition according to the present invention.These'percentages are not to be construed, however, as. limitations butmerely an indication of the range of sulphur in the form defined foroptimum results.

Examples of other sulphur compounds which may be added to anoil base toobtain a sulphur treated oil are the produ'ctsobtained bythe reaction ofan organic halogen compoundwith a sulphur compound, such as for examplethe in- 0:. game-sulphides and polysulphides, resulting in the, completeor partial substitution of a sulphurbearing radicle for the halogen.Examples'of invention t'o proor with such materials are the reactionproducts of sodium sulphide, sodium polysulphide, sodium thiccyanate, orpotassium xanthate with aralkyl chlorides such as:

Benzyl chloride Chlor-benzyl cholorides Xylyl chloride Chlor-xylylchlorides or with alkyl chlorides such as:

Lauryl chloride Cetyl chloride Chlorinated petroleum naphtha Chlorinatedpetroleum wax cycle-aliphatic chlorides such as:

Cyclohexyl-methyl chloride Naphthenyl chloride specifically,chlorinated, carbon ring compounds.

The halogenated oxygen-containing carbon ring compounds added to asulphur treated 011 base are, as above indicated, preferably of thechlorinated species and particularly the followingcompounds have beenfound to produce very satisfactory results, viz: halogenated or moreKetones:

, 'Acetophenone Anthraquinone Benzaphenone Benzil Benzoin Butylbenzophenones ,Camphor Cyclohexanone Di(methy1-phenyl) ketone Dinaphthylketone Dixenyl ketone specifically, chlorinated oxygen-containingsubstituted benzene compounds such as:

Chlorinated phenols Chlorinated cresols Chlorinated diphenyletherChlorinated methyl salicylate halogenated"substituted di-phenyl such as:

Chlorinated P-phenyl phenol Chlorinated di-xenyl ether chlorinatedsubstituted naphthalenes such as:

l Chlorinated 'naphthols;

as well as the aromatic ethers, phenols, acids,

the esters'and the aldehydes.

For many purposes it is particularly advanq tageous touse a halogenatedoxygen-containing carbon-ring compound which contains a carbonyl radiclesuch as the cyclo-aliphatic and aromatic aldehydes, amides, ketones,acids, esters and salts, thin-acids and esters and salts of thio-acids.

Specific examples of preferred compoundsof which the halogen-bearingderivatives may be used for our purpose are as follows: I

Aldehydes:

Benzaldehyde Furfural Phenyl acetaldehyde Lauryl benzaldehyde Amides:

Acetanilide Anilides of naphthenic acids Benzamide' Benzanilide Laurylbenzamides Lauryl benzanilides Naphthenyl ben'zamides Naphthenylbenzanilides Stearanilide Furoin Lauryl benzophenones Methylbenzophenones Methylxenyl ketone Naphthenyl benzene Naphthenyl diphenylsN aphthenyl naphthalenes Stearoyl benzene Stearoyl naphthalenes Stearoyldiphenyls Stearoyl diphenyl ethers Phenyl naphthyl ketone Acids:

. Lauryl toluic acids Este Naphthenyl benzene sulfonic acids Naphthenylbenzoic acids Naphthenyl phenyl acetic acids Naphthenyl salicylic acidsNaphthenyl thiobenzoic acids Naphthenyl toluic acids Phenoxyphenylstearic acid Phenyl acetic acid I Phenyl mercapto stearic acid Phenylpropionic acid Phenyl stearic acid Stearoyl benzene sulfonic acidStearoyl benzoic acids Stearoyl phenyl acetic acids Stearoyl salicylicacids Stearoyl thiobenzoic acids Stearoyl toluic acids Thiobenzoic acidToluic acid Amyl salicylate Benzyl acetate Benzyl benzoate Benzylstearate Butyl azobenzoate Butyl esters of pyrrole carboxylic acid Butylesters of thiophene carboxylic acid Butyl benzoate Butyl thio-benzoateButyl ester or mercapto rosolic acid Butyl ester of phenyl acetic acidEsters-Continued Butyl ester of phenyl stearic acid Butyl furoate Butylmercapto benzoate Butyl toluate Dilauryl phthalate Dibutyl phthalatevEsters of cinnamic acid Esters of diphenyl acetic acid Ethyl ester ofphenyl acetic acid Esters of ethyl salicylic acid Ethyl toluate Estersof phenyl mercaipto stearic acid Esters of phenyl propionic acid Laurylbenzoate Lauryl salicylate Lauryl toluate Lauryl ester of phenyl aceticacid Methyl ester of lauryl salicylic acid Methyl ester of phenylstearic acid Methyl ester of phenyl mercapto stearic acid Methyl esterof naphthenyl benzoic acid Methyl ester of stearoyl benzoic acid Laurylester of phenyl propionic acid Methyl toluate Phenyl acetate Phenylbenzoate Phenyl stearate Salts of organic bases:

Aniline oleate Aniline stearate Benzylamine stearate Dilauryl aminebenzoate Dilauryl amine salt of phenyl stearlc acid Lauryl-pyridinestearate Lauryl-quinoline stearate N-lauryl aniline oleate N-laurylaniline stearate N-lauryl aniline mercapto stearate N-lauryl anilinenaphthenate N-lauryl naphthylamine stearate N-naphthenyl anilinestearate N-naphthenyl butylamine benzoate Salts of inorganic bases:

Aluminum rphenyl mercaptostearate Aluminum phenyl stearate Barium phenylstearate Calcium lauryl thiobenzoate Calcium naphthenyl benzoate Calciumnaphthenyl thiobenzoate Calcium phenyl mercapto stearate Calcium phenylstearate Calcium phenyl thiostearate Calcium stearoyl benzoate Calciumstearoyl thiobenzoate Sodium phenyl mercaptostearate' Sodium phenylstearate Zinc naphthenyl benzoate such as iodine, PCls, iron, etc., orby (b) treating methyl salicylate with PCls, or by (c) esterifyingchlor-salicylic acid with methyl alcohol.

By the term naphthenyl" as used herein, we mean the radicles which havethe structure are added, if a large percentage of such compounds areadded, there will be a tendency to destroy thick-film" lubricationbecause of such reduction in viscosity. If an excessive quantity of suchcompounds are added, all of the lubrication will then be of thethin-film type and therefore produce a decided increase in the amount offriction developed.

Optimum results are obtained by using minimum quantities of thesehalogenated compounds so that their beneficial effect in the region ofthin-film lubrication will not be over-shadowed by their detrimentaleffect in the region of thickfilm lubrication.

Our invention contemplates incorporating with a sulphur treated oil basea total of less than 20% of at least one halogenated oxygen containingcarbon ring compound of the enumerated class.

The optimum amount of they halogenated compound to be employed willdepend. largely upon' the halogen content of the particular compound,its physical characteristics and especially its effect on the viscosityof the oil to which it is added.

The particular use for which the lubricant is intended is also agoverning factor in determining the amount of the compound to be added.

For the purpose of lubricatingand reducing the friction between therelatively movable parts of an .internal combustion engine suchas crankcase bearings, piston and cylinder surfaces, as well as piston rings andvalves, a composition according to our invention comprises a largeproportion of a sulphur treated oil base and concentrations of fromone-half to two per cent of halogenated compounds of the above classcontaining from 50% to 25% of chlorine. of the engine is to belubricated separately from the remainder of the mechanism or by meansacting in an auxiliary fashion, the composition for such purposes willpreferably contain a larger amount of such halogenated compounds, i. efrom 2% to 10%.

The limit of the amount of the halogenated compounds which may be addedto a sulphur treated oil base and which will produce improved resultsdepends, as above indicated, upon the reduction in viscosity of thecomposition caused by the addition of such compounds. Certain of themore viscous compounds, for example, dimethyl dichlor benzophenone, maybe added in amounts exceeding 10% without causing too great a reductionof viscosity. In any event, the resultant composition will have inferiorlubricating proper;

ties if the loss of viscosity is too great as will result from the useof more than 20% of halogenated compounds of any type.

' It has been found that for optimum results a certain relationshipshould be maintained be- If the valve structure tween the amount ofchlorine and the amount of sulphur, when the halogenated compounds ofthe above class are added toa sulphur treated oil. It has been foundthat to an oil base having a low content; of sulphur in active orloosely combined form, halogenated compounds should be added incorrespondingly low concentrations for best results.

When the halogenated compounds of the above class addedto the sulphurtreated oil base are of the closed ring type in contradistinction to theopen chain type, certain advantages are obtained which may be brieflyexplained as follows:

In case of oil in actual use in machinery of any kind and particularlyin the crank case of internal combustion. engines, moisture is usuallypresent to some extent and due to condensation may even which readilyhydrolize, such as chlorinated open chain compounds, areadded to thesulphur treated oil base, hydrolysis may take place tosuch an extentthat the metal parts of'any machine being lubricated will be seriouslyattacked and corroded by the acid generated. On the other hand, theaddition of chlorinated carbon ring compounds of the above. enumeratedclass does not cause corrosion, particularly when such compounds are ofthe type in which the halogen is directly attached to a benzenold ring,

The oil base of our lubricating compositions is a lubricating oil of thetype best suited for the particular use for which the ultimatecomposition of our invention are designed for the lubrication ofautomobiles, the. oilbase will of course preferably consist of a refinedmineral lubricating oil is designed. When the lubricating compositionsof lubricating viscosity for the particular point of application. Inother words, the conventional gear oil may be used for the lubricationof gears; for example, mineral oil having a viscosity range of from anS. A. E. 80 to an S. A. E. 140. Generally a lighter, more highly refinedoil may be used in the crank case, such as a motor oil having aviscosity range of from an S. A E. 10 to an S. A. E. 50.

This'lnvention is applicable to lubricating compositions in which thebase may consist either entirely or in part of synthetic oils,hydrogenated oils, and voltolized oils.

The oil base may also desirably contain other a well known constituentssuch as those which improve the oiliness, pour point, cold test, andoxidation properties, etc., of the oil. In general compositions of ourinvention may be employed w th any commercially available additionagents for the above defined purposes since they are generallycompatible with the same in the amounts usually used. 1

The composition comprising our invention has certain advantages whenused as a lubricant" of which the following may be mentioned:

First: By the use of this composition it is possible to extend thepressure range between the bearing surfaces because of the reducedtendency for bearing surfaces so lubricated to become scored or to seizeat higher pressures than are allowable with ordinary lubricants.

Second: The friction between the bearing surfaces is reduced, especiallyin the higher prescially if the incorporation is effected in the mannerdescribed in Cornell Patent No. 2,042,880. and since quite smallpercentages often give remarkably improved results, it is seldom ofextreme importance that the addition agents be oil-soluble in allproportions.

The addition agents above enumerated for use in my compounded lubricantsinclude certain ones which may be found to at least partially decomposeunder conditions of extremestress such as the very high temperatureencountered in certain'classes of use, while others are quitestable'even under such extreme conditions.

The use for which the lubricant is designed therefore determines theparticular type of addition agent to be selected. A certain amount ofdecomposition, which proceeds at a relatively slow rate, is usually notharmful. Care should be exercised, however, to select for a particularset of operating conditions, an addition agent which in the .011 baseused will not decompose under such operating conditions except at a lowrate.

By the term stable as used herein in describing the addition agents: ismeant the characteristics of the addition agents which enables them toresist decomposition in the oil under the condition of use for which thelubricating composition is designed.

In view of the particular uses for which my compounded lubricants areintended, it is apparent that of the materials included in the foregoingenumeration of the addition agents which may be employed, those whichare readily lubricants for internal combustion engines, they shouldpreferably be stable to the extent where there will be substantially nodecomposition, when the lubricating composition is exposed totemperatures up to 250 F.

With regard to the use of sulphur treated oil in combination withhalogenated compounds, it should be noted that for sufiicientlydesirable results, the major proportion of the ultimate composition neednot consist entirely of sulphurtreated .oil, but a suitable oil basesuch as mineral oil may have added thereto minor quantities orproportions of either a sulphur treated oil I d, and a halogenated com-7 or a sulphur compou pound. I

This application is a continuation in part of copending applicationSerial No. 744,600, filed September 17, 1934, which was in turn acontinuation of application plication Serial No. 737,070, filed July 26,1934) Other modes of applying the principle ofthe Serial No. 649,734,filed December 31, 1932, now Patent No. 2,213,532, and.

invention may be employed, change being made as regards the detailsdescribed, provided the features stated in any of the following claimsor the equivalent of such be employed.

We therefore particularly point out and distinctly claim as ourinvention:

1. A lubricating composition comprising a major proportion of minerallubricating oil and minor amounts of both a sulphur treated oil and astable oil-soluble halogen bearing organic ring 10 compound containing acarbonyl radicle.

2. A lubricating composition comprising a major proportion of minerallubricating oil and minor amounts of both a sulphur treated oil and astable oil-soluble halogen bearing aromatic compound containing acarbonyl radicle.

3. A lubricating composition comprising a major proportion .of mineraloil and minor amounts of both a sulphur treated oil and a

